Corrigendum #9

[Shawn Steele]

> I should note that this front-end to 'diff' changes the input files, writes the modified versions out, and calls 'diff' with those modified files as its inputs.  By using noncharacters, it would be depending on 'diff' to 1) not use them, and 2) to not filter them out, and 3) for the system to be able to store and retrieve them in files.

In my view that is still "internal" to your apps use of these characters :)

The original text doesn't say that my application cannot store & retrieve them from files for internal use.  On the contrary, I'd expect proprietary formats for internal use to require that.  I agree that the original text is a bit vague on the question of tools to inspect/modify/whatever your internal use.

-Shawn